Jupiter 05.16.04

Hi,

I had roughly average to slightly better than average for observing Jupiter. The accompanying sketch doesn't really show anything unusual. I think that's Callisto which appeared rather dark against the NNTeB.

What was unusual is that I used the 4.4" ,(112 m.m.), aperture stop with my scope. In concert with my Chromacor II, the effective focal ratio is at f/10. I guess I just wanted to see what kind of detail I could pick up on at a smaller aperture.

Best, Sol Robbins

Attached Image:

Great sketch Sol, I saw Jupiter at 10:00 CST and saw Callisto emerge from Jupiter's disk, I also saw a transit of the grs,sketch to follow, ironically I nearly always use the aperture mask on my 6" achro as it improves contrast, tonight however Jupiter looked better without it,I can see the grs peaking around the corner on your sketch your detail is just fantastic.

Sol,

Thanks for sharing your excellent observation of Jupiter. You have still picked up a good amount of detail over the disk although you used an aperture stop. A well made 4-inch refractor is an excellent instrument for use on the planets and Moon. Looking forward to your future observations.

Carlos